Could we see a galaxy that is 20 billion
No, because it would be beyond the bounds of our observable universe.
What do astronomers mean by the Big
The event that marked the beginning of the expansion of the universe
Suppose you live in the United States and you
see a crescent moon in your evening sky tonight. What will a friend in South
America see tonight?
Your friend will also see a crescent moon.
Which of these discoveries of Galileo
contradicted the idea that everything orbited the Earth?
Moons revolving around Jupiter.
Copernicus's model of the solar system gave
much better predictions than the model of Ptolemy.
Where is our solar system located within the
Milky Way Galaxy?
Roughly halfway between the center and the edge of the visible disk of the galaxy
How does Earth's varying distance from the Sun
affect our seasons?
It doesn't; Earth's orbital distance plays no significant role in the seasons.
We describe a location on Earth's
surface by stating its ________.
latitude and longitude
From the fact that virtually every galaxy is
moving away from us and more distant galaxies are moving away from us at a
faster rate than closer ones, we conclude that
the universe is expanding.